Reducing the undesirable solids and analytes in raw wastewater has been tried for a number of years. The raw wastewater or influent would enter a primary treatment facility to remove the large particle contaminants in the raw wastewater. The primary treated wastewater would then be sent to a secondary treatment facility in order to lower the total suspended solids (TSS) and reduce the biochemical oxygen demand (BOD) in that wastewater. In the primary and the secondary treatments, nitrogen and phosphorous are coincidentially reduced.
However, eutrophication caused by nitrogen and phosphorous has resulted in serious environmental degradation of many lakes, rivers and even large bodies of water, such as, for example, the Long Island sound. The known secondary treatment facilities, except when needed for microbiological metabolism, do not normally direct themselves to the reduction of nitrogen (N) and phosphorous (P).
More recently, a tertiary treatment or third treatment step that employs physical-chemical or biological process followed by chemical precipitation has been used to lower the concentration of these analytes. To remove the nitrogen and phosphorous in the known tertiary treatment processes has been found costly. The tertiary treatment processing units have also been found to require a significant area in a facility.
The present tertiary process increases the amount of TSS, BOD, and the analytes nitrogen and phosphorous, removed from influent over known tertiary treatment units and processes. The present tertiary treatment process can also remove bacteria and viruses much more effectively than present systems.
The present treatment unit can be used as a wastewater enhanced treatment, drinking water treatment, industrial wastewater enhanced treatment, and in-lake revitalization. It is versatile and requires a very small area as compared to the prior art treatment units. It is adaptable and can fit existing plant operations, as well as complying with present government regulatory or permit requirements.
The prior art treatment units fail to provide the combination of treatment units or stations provided in the present treatment unit. Furthermore, the precise steps of the present treatment process are absent in the prior art processes.
For example, some prior art units and processes provide breakpoint chlorination or superchlorination that is accomplished by the addition of chlorine to the effluent or wastewater stream in an amount sufficient to oxidize the ammonia-nitrogen to nitrogen gas. After sufficient chlorine is added to oxidize the organic matter and other readily oxidizable substances present, a stepwise reaction of the chlorine with ammonium takes place. Such breakpoint chlorination is shown in U.S. Pat. No. 3,733,266 titled: Waste Water Purification By Breakpoint Chlorination and Carbon Adsorption, which issued on May 15, 1973 to D.F. Bishop, et al. This patent is directed to a method of purification of wastewater in which sodium hypochlorite or chlorine is used to oxidize the ammonia in raw, secondary lime clarified wastewaters using breakpoint chlorination. The sodium hypochlorite or chlorine is added to the influent and mixed therein by a mixer-reactor, then the influent, now effluent, passes a carbon adsorption station or step to provide the resultant effluent.
U.S. Pat. No. 3,760,829 titled: Automatic Control System For The Safe and Economical Removal of NH3 by Breakpoint Chlorination, which issued on Sep. 25, 1973 to W.W. Schuk, et al., is directed to an automatic system for controlling the chlorine feed in a breakpoint chlorination process. See also, U.S. Pat. No. 4,435,291 titled: Breakpoint Chlorination Control System, which issued on Mar. 6, 1984 to T.N. Matsko.
U.S. Pat. No. 4,948,510 titled: Biological Phosphorous Removal From Wastewater Using Multiple Recombinable Basins, which issued on Aug. 14, 1990 to M.D. Todd, et al., is directed to a process for removing phosphorous, as well as lowering the amounts of ammonia, TSS and BOD levels. The treatment cycle of this process provides multiple basins that may be individually controlled to achieve anaerobic, anoxic or aerobic conditions to optimize the growth of phosphorous storing microorganisms, and thus cause the uptake of phosphorous by the organisms and also provide for the microbiological nitrification of ammonia.
U.S. Pat. No. 4,366,064 titled: Treatment of Blast Furnace Wastewater to Mihelic, et al., is directed to a method used to treat blast furnace and other wastewater containing ammonia, cyanide and phenol by a breakpoint chlorination. An activated carbon step is provided to remove residual contaminants.
Japanese citation No. 61-39877 provides a method for treating phosphate-containing water by placing the water in contact with calcium phosphate-containing seed crystal and with activated alumina.
Thus, the prior art fails to address the combined removal of BOD, TSS, nitrogen and phosphorous in a single system. The prior art also fails to provide the combination and sequence of operations in the treatment unit and steps in the present systematic tertiary treatment process. In addition, the prior art fails to provide the versatility of the subprocesses of the present process.
Against the foregoing background, it is a primary object of the present invention to provide a treatment system or unit and process that reduces in influent the levels of TSS, BOD, nitrogen, phosphorous, bacteria and viruses.
The preferred treatment unit and process is a systematic tertiary treatment unit and process that also removes bacteria and viruses.
The present invention provides a tertiary treatment unit and process that are versatile.
The present invention further provides a tertiary treatment system or unit that requires a relatively small area, and is adaptable so that it can readily fit into existing plants.
An alternative embodiment of the present invention is a tertiary treatment unit and process therefore to remove TSS and BOD from an influent which unit and process include two filtration units and an adsorption unit.
Another alternative embodiment of the present invention is a tertiary treatment unit and process therefore to remove TSS, BOD and nitrogen from an influent which unit and process include two filtration units, means for supplying chemicals, an in-line mixer for mixing the chemicals into the effluent in the unit, a reactor and an adsorption unit.